Below are test results froma very technically-savvy customer: He is testing comparing against the AWUS036H, which is a 802.11G device – and so this is not really conclusive with regard to how the AWUS036NHA performs in 802.11n mode – but it is interesting regarding the performance of the AWUS036NH in 802.11G mode:

CUSTOMER’S COMMENTS (all below):

The signal strengths I see with the HA are typically not as strong as what I see with the H. However, this can be misleading since the driver that the manufacturer writes controls this value, and from working on the 8187l driver, I know that it tends to be a bit optimistic. So this in itself is not really too important. They both saw about the same networks. There was some variation at times, with the H tending to see a few more. Again, this fact alone is not that important however, but consumers tend to like devices that show lots of networks, even if they can’t connect to them J.

I connected both the H and the HA to an Engenius AP so I could monitor the signal level of both devices. This AP is about ¾ mile from me, and I am using just the standard 5db rubber antenna’s that ship with each unit.

The HA was typically giving a signal strength, on the Engenius AP, of around -78 to -82. As low as -90db.
The H was typically giving a signal strength, on the Engenius AP, of around -73 to -80. As low as -88db.

So, the H seemed to have a bit higher output, in this particular test. But not substantially.

They were both able to connect to the same set of networks where I am currently located, however I need to test this in more locations which will happen as we start to move the boat in 2 weeks. My current location is pretty limited so I don’t think there is anything conclusive from this yet.